If you’re dealing with a runny nose, uncontrollable sneezing, or red, watery, and itchy eyes, you likely only want one thing: relief. Thankfully, there are a range of over-the-counter (OTC) drugs that work well to treat seasonal allergies (hay fever). Benadryl is a popular option for many people.

Benadryl is the brand-name version of an antihistamine called diphenhydramine. An antihistamine is a drug that interferes with the action of the compound histamine in your body.

Histamine is involved in your body’s immune response to allergens. It’s the reason you get a stuffy nose, itchy skin, and other reactions when you come in contact with something you’re allergic to. An antihistamine works by blocking your body’s response to these allergens. This can ease your allergy symptoms.

Because you can purchase Benadryl at pharmacies and grocery stores without a prescription, you might think it’s safe to use in any situation. But Benadryl is a strong drug, and it comes with risks. One risk is the severe effects it can cause if you take it with alcohol.

Benadryl doesn’t affect your liver like alcohol does. But both drugs work on your central nervous system (CNS), which is made up of your brain and spinal cord. That’s the problem.

Benadryl and alcohol are both CNS depressants. These are drugs that slow down your CNS. Taking them together is dangerous because they can slow down your CNS too much. This can cause drowsiness, sedation, and trouble doing physical and mental tasks that require alertness.

In short, Benadryl and alcohol shouldn’t be used together. It’s important to know, though, that it’s especially risky to use them together in certain cases. These cases include if you misuse Benadryl, if you take these drugs together while driving, and if you’re a senior.

Misuse

Benadryl is approved to treat allergy symptoms only. It’s not meant to be used for any other purpose.

However, some people may think it’s a good idea to use it as a sleep aid. This is because Benadryl causes drowsiness. In fact, the generic form of Benadryl, diphenhydramine, is approved as a sleep aid. Some people may think alcohol can serve the same role, since it can also make you sleepy.

But if you really want to get a good night’s sleep, don’t make the mistake of thinking a glass of wine and a dose of Benadryl will do the trick. This misuse of Benadryl and alcohol may actually make you dizzy and prevent you from sleeping through the night.

Benadryl may also interact negatively with sleep aids and other medications. So, to be safe, you should only use Benadryl to treat your allergy symptoms.

Driving warning

You may have heard that you shouldn’t drive or use machinery if you take Benadryl (alone or with alcohol). This warning is because of the risks of CNS depression from the drug.

In fact, the National Highway Traffic Safety Administration suggests that Benadryl may have a greater effect on a driver’s ability to stay alert than alcohol does. The administration also agrees that alcohol can enhance the effects of Benadryl.

You already know that drinking alcohol and driving is dangerous. Add Benadryl to the mix, and the behavior becomes even riskier.

In seniors

Drinking alcohol and taking Benadryl makes it harder to control body movement well for people of all ages. But it may be even riskier for seniors.

Impaired motor ability, combined with the dizziness and sedation from Benadryl, can cause particular problems for older adults. For instance, the combination may increase the risk of falls in seniors.

Now that you know that Benadryl and alcohol don’t mix, you should be aware of sources of hidden alcohol that you should avoid while taking Benadryl.

Some medications may actually contain alcohol. These include drugs such as laxatives and cough syrup. In fact, some medications are up to 10 percent alcohol. These drugs may interact with Benadryl. Be sure to read the labels on all the drugs you’re taking to reduce your risk of accidental interactions or misuse.

If you’re taking more than one OTC or prescription drug or supplement, talk to your doctor or pharmacist. They can let you know if your other medications contain alcohol and if it’s safe to take them with Benadryl.

Benadryl is a strong drug. Using it safely means not drinking alcohol while you take it. Combining the drug with alcohol can cause dangerous effects, such as extreme drowsiness and impaired motor skills and alertness.

Benadryl is designed for short-term use, so it’s best to simply wait until you’re done taking it before you have any alcohol. This includes beverages, mouthwashes, and other drugs that list alcohol as an ingredient. To be on the safe side, you can ask your doctor or pharmacist how long to wait after you finish taking Benadryl before you reach for a drink.

If you drink a lot and find it difficult to hold off on drinking for a few days, consider reading up on resources and support.

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